WIP: Lots of networking niggly bits and JNI stuff and uuugh

src/main/java/swiss/qpq/gajumaru/core/crypto/Vault.java

@@ -20,6 +20,7 @@
 
 package swiss.qpq.gajumaru.core.crypto;
 
+import java.security.SecureRandom;
 import javax.crypto.Cipher;
 import javax.crypto.SecretKey;
 import javax.crypto.spec.GCMParameterSpec;
@@ -32,6 +33,7 @@ public final class Vault {
 
     private static final String AES_GCM = "AES/GCM/NoPadding";
     private static final int GCM_TAG_LENGTH = 128; // Bits
+    private static final int IV_LENGTH = 12; // Bytes
 
     private Vault() {}
 
@@ -53,33 +55,53 @@ public final class Vault {
 
     /**
      * Encrypts plaintext using AES/GCM.
-     * Letting the provider generate the IV (required by Android Keystore).
+     * Manually generates the IV to ensure deterministic tag length and cross-provider consistency.
      */
     public static Ciphertext encrypt(SecretKey key, byte[] plaintext) throws Exception {
-        Cipher cipher = Cipher.getInstance(AES_GCM);
-        cipher.init(Cipher.ENCRYPT_MODE, key);
-        byte[] iv = cipher.getIV();
-        byte[] ciphertext = cipher.doFinal(plaintext);
-        return new Ciphertext(iv, ciphertext);
+        try {
+            byte[] iv = new byte[IV_LENGTH];
+            new SecureRandom().nextBytes(iv);
+            
+            Cipher cipher = Cipher.getInstance(AES_GCM);
+            GCMParameterSpec spec = new GCMParameterSpec(GCM_TAG_LENGTH, iv);
+            cipher.init(Cipher.ENCRYPT_MODE, key, spec);
+            
+            byte[] ciphertext = cipher.doFinal(plaintext);
+            return new Ciphertext(iv, ciphertext);
+        } catch (Exception e) {
+            String msg = e.getMessage();
+            if (msg == null) msg = e.toString();
+            throw new Exception("Vault.encrypt failed: " + msg, e);
+        }
     }
 
     /**
      * Encrypts plaintext using AES/GCM with a specific IV.
      */
     public static byte[] encrypt(SecretKey key, byte[] iv, byte[] plaintext) throws Exception {
-        Cipher cipher = Cipher.getInstance(AES_GCM);
-        GCMParameterSpec spec = new GCMParameterSpec(GCM_TAG_LENGTH, iv);
-        cipher.init(Cipher.ENCRYPT_MODE, key, spec);
-        return cipher.doFinal(plaintext);
+        try {
+            Cipher cipher = Cipher.getInstance(AES_GCM);
+            GCMParameterSpec spec = new GCMParameterSpec(GCM_TAG_LENGTH, iv);
+            cipher.init(Cipher.ENCRYPT_MODE, key, spec);
+            return cipher.doFinal(plaintext);
+        } catch (Exception e) {
+            throw new Exception("Vault.encrypt(iv) failed: " + e.getClass().getName() + ": " + e.getMessage(), e);
+        }
     }
 
     /**
      * Decrypts ciphertext using AES/GCM.
      */
     public static byte[] decrypt(SecretKey key, byte[] iv, byte[] ciphertext) throws Exception {
-        Cipher cipher = Cipher.getInstance(AES_GCM);
-        GCMParameterSpec spec = new GCMParameterSpec(GCM_TAG_LENGTH, iv);
-        cipher.init(Cipher.DECRYPT_MODE, key, spec);
-        return cipher.doFinal(ciphertext);
+        try {
+            Cipher cipher = Cipher.getInstance(AES_GCM);
+            GCMParameterSpec spec = new GCMParameterSpec(GCM_TAG_LENGTH, iv);
+            cipher.init(Cipher.DECRYPT_MODE, key, spec);
+            return cipher.doFinal(ciphertext);
+        } catch (Exception e) {
+            String msg = e.getMessage();
+            if (msg == null) msg = e.toString();
+            throw new Exception("Vault.decrypt failed: " + msg, e);
+        }
     }
 }

src/main/java/swiss/qpq/gajumaru/core/tools/Grids.java

@@ -79,6 +79,7 @@ public final class Grids {
     }
 
     public static ParseResult parse(String gridsUrl) {
+        android.util.Log.i("Grids", "Parsing URL: " + gridsUrl);
         try {
             URI uri = new URI(gridsUrl);
             String scheme = uri.getScheme();
@@ -86,6 +87,8 @@ public final class Grids {
             String path = uri.getPath();
             String query = uri.getQuery();
 
+            android.util.Log.i("Grids", "Components: scheme=" + scheme + ", host=" + host + ", path=" + path);
+
             if (!"grids".equals(scheme) && !"grid".equals(scheme)) {
                 throw new IllegalArgumentException("Invalid scheme: " + scheme);
             }
@@ -104,10 +107,10 @@ public final class Grids {
                 String location = host + (uri.getPort() != -1 ? ":" + uri.getPort() : "");
                 return ParseResult.transfer(Context.NODE, location, recipient, amount, payload);
             } else if (path.startsWith("/1/d/")) {
-                String subPath = path.substring(5);
+                String subPath = path.substring(4); // Includes the leading slash
                 String httpScheme = "grids".equals(scheme) ? "https" : "http";
-                String baseUrl = httpScheme + "://" + host + (uri.getPort() != -1 ? ":" + uri.getPort() : "") + subPath;
-                String httpUrl = query != null ? baseUrl + "?" + query : baseUrl;
+                String hostPart = host + (uri.getPort() != -1 ? ":" + uri.getPort() : "");
+                String httpUrl = httpScheme + "://" + hostPart + subPath + (query != null ? "?" + query : "");
                 return ParseResult.sign("grids".equals(scheme) ? Context.HTTPS : Context.HTTP, httpUrl);
             } else {
                 throw new IllegalArgumentException("Unknown verb in path: " + path);
@@ -118,8 +121,8 @@ public final class Grids {
     }
 
     public static final String REQ_TYPE_MESSAGE = "message";
+    public static final String REQ_TYPE_BINARY  = "binary";
     public static final String REQ_TYPE_TX      = "tx";
-    public static final String REQ_TYPE_ACK     = "ack";
 
     public static Map<String, Object> makeRequest(String type, Object payload, String publicId, String networkId) {
         Map<String, Object> req = new LinkedHashMap<>();

src/main/java/swiss/qpq/gajumaru/core/tools/Http.java

@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2026 QPQ AG <info@qpq.swiss>. All rights reserved.
+ * Project: Gajumaru Core Java Libraries <gajumaru.io>
+ *
+ * This program is dual-licensed:
+ * 1) Under the GNU Affero General Public License as published by the Free
+ *    Software Foundation, either version 3 of the License, or (at your option)
+ *    any later version (AGPL-3.0-or-later).
+ *
+ * 2) Under a commercial/proprietary license available directly from QPQ AG.
+ *    If you wish to use this software outside the strict constraints of the
+ *    AGPLv3 (e.g. within a closed-source or proprietary product), you must
+ *    purchase a commercial license from QPQ AG.
+ *
+ * Authors:
+ *   - Craig Everett <craigeverett@qpq.swiss>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later OR LicenseRef-QPQ-Commercial
+ */
+
+package swiss.qpq.gajumaru.core.tools;
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+import swiss.qpq.gajumaru.core.encoding.ZJ;
+
+// Minimal HTTP client for GRIDS and Node interaction.
+
+public final class Http {
+
+    private Http() {}
+
+    public static Object get(String url) throws Exception {
+        return request(url, "GET", null);
+    }
+
+    public static Object post(String url, Object body) throws Exception {
+        return request(url, "POST", body);
+    }
+
+    private static Object request(String urlStr, String method, Object body) throws Exception {
+        android.util.Log.i("Http", "Request [" + method + "]: " + urlStr);
+        URL url = new URL(urlStr);
+        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
+        conn.setRequestMethod(method);
+        conn.setConnectTimeout(15000);
+        conn.setReadTimeout(15000);
+        conn.setInstanceFollowRedirects(true);
+        
+        // Emulate a standard browser agent to avoid being blocked by strict servers
+        conn.setRequestProperty("Accept", "application/json, text/plain, */*");
+        conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Linux; Android 10) GajuMobile/1.0");
+
+        if (body != null) {
+            conn.setRequestProperty("Content-Type", "application/json");
+            conn.setDoOutput(true);
+            try (OutputStream os = conn.getOutputStream()) {
+                byte[] input;
+                if (body instanceof String) {
+                    input = ((String) body).getBytes(StandardCharsets.UTF_8);
+                } else {
+                    input = ZJ.encode(body).getBytes(StandardCharsets.UTF_8);
+                }
+                os.write(input, 0, input.length);
+            }
+        }
+
+        int code = conn.getResponseCode();
+        android.util.Log.i("Http", "Response Code for " + urlStr + ": " + code);
+        
+        StringBuilder response = new StringBuilder();
+        try (java.io.InputStream is = (code >= 200 && code < 300) ? conn.getInputStream() : conn.getErrorStream();
+             BufferedReader br = new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_8))) {
+            String line;
+            while ((line = br.readLine()) != null) {
+                response.append(line).append("\n");
+            }
+        }
+
+        String responseStr = response.toString().trim();
+        
+        if (code < 200 || code >= 300) {
+            String reason = "HTTP " + code;
+            try {
+                Object decoded = ZJ.decode(responseStr);
+                if (decoded instanceof Map) {
+                    Object r = ((Map<?, ?>) decoded).get("reason");
+                    if (r != null) reason = r.toString();
+                }
+            } catch (Exception ignored) {}
+            throw new Exception(reason + " (URL: " + urlStr + ")");
+        }
+
+        if (responseStr.isEmpty()) return null;
+
+        try {
+            return ZJ.decode(responseStr);
+        } catch (Exception e) {
+            if (responseStr.startsWith("<")) {
+                android.util.Log.e("Http", "Server returned HTML for " + urlStr + ". Body preview: " + 
+                    (responseStr.length() > 500 ? responseStr.substring(0, 500) : responseStr));
+                throw new Exception("Server returned HTML instead of JSON. Full URL and body logged to Logcat.");
+            }
+            throw new Exception("JSON parse failed for " + urlStr + ": " + e.getMessage());
+        }
+    }
+}

src/main/java/swiss/qpq/gajumaru/core/tools/NodeClient.java

@@ -20,32 +20,14 @@
 
 package swiss.qpq.gajumaru.core.tools;
 
-import java.io.BufferedReader;
-import java.io.InputStreamReader;
-import java.io.OutputStream;
-import java.net.HttpURLConnection;
-import java.net.URL;
-import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
 import java.util.HashMap;
-import swiss.qpq.gajumaru.core.encoding.ZJ;
-
-
-// NodeClient provides a simple interface to query Gajumaru nodes.
-// Ported from hz.erl
-//
-// Conceptually very similar to Hakuzaru's main interface, but (at least currently)
-// more limited (no contract deployment, call, etc.). The most obvious difference is that
-// instead of gm-java being a stateful service the way hz can be, this is a pure library
-// and the caller is expected to be the one that is keeping track of a list of possible
-// endpoints.
-//
-// This design will evolve in the future as the concept of network and inter-network
-// crawling evolves (and obviously as ACs are introduced). In this iteration, though,
-// my goal is to keep things as simple as possible, and that is why this is probably
-// somewhat unidiomatic for Java (I don't *really* know, but this works).
 
+/**
+ * NodeClient provides a simple interface to query Gajumaru nodes.
+ * Ported from hz.erl
+ */
 public final class NodeClient {
 
     public static final class Endpoint {
@@ -65,7 +47,6 @@ public final class NodeClient {
     }
 
     private final List<Endpoint> endpoints;
-    private int timeout = 5000;
 
     public NodeClient(List<Endpoint> endpoints) {
         if (endpoints == null || endpoints.isEmpty()) {
@@ -74,10 +55,6 @@ public final class NodeClient {
         this.endpoints = endpoints;
     }
 
-    public void setTimeout(int timeout) {
-        this.timeout = timeout;
-    }
-
     public Map<String, Object> status() throws Exception {
         return (Map<String, Object>) request("/v3/status", "GET", null);
     }
@@ -121,15 +98,19 @@ public final class NodeClient {
         Exception lastException = null;
         for (Endpoint endpoint : endpoints) {
             try {
+                String protocol = endpoint.useTls ? "https://" : "http://";
+                String url = protocol + endpoint.host + ":" + endpoint.port + path;
+                
                 if (endpoint.useTls) {
                     try {
-                        return performRequest(endpoint, path, method, body, true);
+                        return "GET".equals(method) ? Http.get(url) : Http.post(url, body);
                     } catch (Exception e) {
                         // Fallback to HTTP
-                        return performRequest(endpoint, path, method, body, false);
+                        String httpUrl = "http://" + endpoint.host + ":" + endpoint.port + path;
+                        return "GET".equals(method) ? Http.get(httpUrl) : Http.post(httpUrl, body);
                     }
                 } else {
-                    return performRequest(endpoint, path, method, body, false);
+                    return "GET".equals(method) ? Http.get(url) : Http.post(url, body);
                 }
             } catch (Exception e) {
                 lastException = e;
@@ -137,46 +118,4 @@ public final class NodeClient {
         }
         throw new Exception("All endpoints failed. Last error: " + (lastException != null ? lastException.getMessage() : "unknown"), lastException);
     }
-
-    private Object performRequest(Endpoint endpoint, String path, String method, Object body, boolean useTls) throws Exception {
-        String protocol = useTls ? "https://" : "http://";
-        String urlStr = protocol + endpoint.host + ":" + endpoint.port + path;
-        URL url = new URL(urlStr);
-        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
-        conn.setRequestMethod(method);
-        conn.setConnectTimeout(timeout);
-        conn.setReadTimeout(timeout);
-        conn.setRequestProperty("Accept", "application/json");
-
-        if (body != null) {
-            conn.setRequestProperty("Content-Type", "application/json");
-            conn.setDoOutput(true);
-            try (OutputStream os = conn.getOutputStream()) {
-                byte[] input = ZJ.encode(body).getBytes(StandardCharsets.UTF_8);
-                os.write(input, 0, input.length);
-            }
-        }
-
-        int code = conn.getResponseCode();
-        StringBuilder response = new StringBuilder();
-        try (BufferedReader br = new BufferedReader(new InputStreamReader(
-                code >= 200 && code < 300 ? conn.getInputStream() : conn.getErrorStream(), 
-                StandardCharsets.UTF_8))) {
-            String line;
-            while ((line = br.readLine()) != null) {
-                response.append(line.trim());
-            }
-        }
-
-        Object decoded = ZJ.decode(response.toString());
-        if (code < 200 || code >= 300) {
-            String reason = "HTTP " + code;
-            if (decoded instanceof Map) {
-                Object r = ((Map<?, ?>) decoded).get("reason");
-                if (r != null) reason = r.toString();
-            }
-            throw new Exception(reason);
-        }
-        return decoded;
-    }
 }

src/main/java/swiss/qpq/gajumaru/core/tools/TransactionService.java

@@ -24,19 +24,23 @@ import java.math.BigInteger;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
 import swiss.qpq.gajumaru.core.crypto.Blake2b;
-import swiss.qpq.gajumaru.core.crypto.Ed25519;
+import swiss.qpq.gajumobile.security.GajuNative;
 import swiss.qpq.gajumaru.core.data.Id;
 import swiss.qpq.gajumaru.core.data.SignedTx;
 import swiss.qpq.gajumaru.core.data.SpendTx;
 import swiss.qpq.gajumaru.core.encoding.ApiEncoder;
 
-// This is where the gnarly mess used to generate transactions lives for now.
-// They might not stay here, but this is where they are for now.
-
+/**
+ * TransactionService provides high-level tools to build and sign transactions
+ * and other chain data.
+ */
 public final class TransactionService {
 
     private TransactionService() {}
 
+    /**
+     * Builds and signs a Spend transaction using a 32-byte seed.
+     */
     public static String buildSpendTx(
         String networkId,
         String senderId,
@@ -47,12 +51,11 @@ public final class TransactionService {
         long ttl,
         long nonce,
         String payload,
-        byte[] seckey
+        byte[] seed
     ) {
         // 1. Decode IDs
         Id sender = new Id(Id.Tag.ACCOUNT, ApiEncoder.decode(senderId).payload());
         
-        // Recipient can be ak_ (account) or ct_ (contract)
         ApiEncoder.DecodeResult recipientResult = ApiEncoder.decode(recipientId);
         Id.Tag recipientTag = recipientResult.type() == ApiEncoder.Type.CONTRACT_PUBKEY ? Id.Tag.CONTRACT : Id.Tag.ACCOUNT;
         Id recipient = new Id(recipientTag, recipientResult.payload());
@@ -69,13 +72,78 @@ public final class TransactionService {
         System.arraycopy(networkIdBytes, 0, networkHash, 0, networkIdBytes.length);
         System.arraycopy(txHash, 0, networkHash, networkIdBytes.length, txHash.length);
         
-        // 4. Sign
-        byte[] signature = Ed25519.sign(seckey, networkHash);
+        // 4. Expand Seed and Sign
+        byte[] keypair = GajuNative.cryptoSignSeedKeypair(seed);
+        if (keypair == null) throw new RuntimeException("Native keypair generation failed");
+        
+        byte[] secretKey = new byte[64];
+        System.arraycopy(keypair, 32, secretKey, 0, 64);
+        
+        byte[] signature = GajuNative.cryptoSignDetached(networkHash, secretKey);
+        
+        GajuNative.memzero(keypair);
+        GajuNative.memzero(secretKey);
+        
+        if (signature == null) throw new RuntimeException("Native signing failed");
         
         // 5. Wrap in SignedTx
         SignedTx signedTx = new SignedTx(List.of(signature), serializedTx);
         
-        // 6. Encode for API
+        return ApiEncoder.encode(ApiEncoder.Type.TRANSACTION, signedTx.serialize());
+    }
+
+    /**
+     * Signs a message using the Gajumaru standard (prefixed and hashed).
+     * @param secretKey 64-byte expanded secret key.
+     */
+    public static byte[] signMessage(String message, byte[] secretKey) {
+        byte[] msgBytes = message.getBytes(StandardCharsets.UTF_8);
+        byte[] prefix = "Gajumaru Signed Message:\n".getBytes(StandardCharsets.UTF_8);
+        
+        byte[] pSize = VarInt.encode(prefix.length);
+        byte[] mSize = VarInt.encode(msgBytes.length);
+        
+        byte[] smashed = new byte[pSize.length + prefix.length + mSize.length + msgBytes.length];
+        int pos = 0;
+        System.arraycopy(pSize, 0, smashed, pos, pSize.length); pos += pSize.length;
+        System.arraycopy(prefix, 0, smashed, pos, prefix.length); pos += prefix.length;
+        System.arraycopy(mSize, 0, smashed, pos, mSize.length); pos += mSize.length;
+        System.arraycopy(msgBytes, 0, smashed, pos, msgBytes.length);
+        
+        byte[] hashed = Blake2b.hash(smashed, 32);
+        return GajuNative.cryptoSignDetached(hashed, secretKey);
+    }
+
+    /**
+     * Signs binary data using the Gajumaru standard (prefixed and hashed).
+     * @param secretKey 64-byte expanded secret key.
+     */
+    public static byte[] signBinary(byte[] data, byte[] secretKey) {
+        byte[] prefix = "Gajumaru Signed Binary:".getBytes(StandardCharsets.UTF_8);
+        byte[] target = new byte[prefix.length + data.length];
+        System.arraycopy(prefix, 0, target, 0, prefix.length);
+        System.arraycopy(data, 0, target, prefix.length, data.length);
+        
+        byte[] hashed = Blake2b.hash(target, 32);
+        return GajuNative.cryptoSignDetached(hashed, secretKey);
+    }
+
+    /**
+     * Signs a transaction.
+     * @param secretKey 64-byte expanded secret key.
+     */
+    public static String signTx(byte[] txData, String networkId, byte[] secretKey) {
+        byte[] nidBytes = networkId.getBytes(StandardCharsets.UTF_8);
+        byte[] hash = Blake2b.hash(txData, 32);
+        
+        byte[] networkHash = new byte[nidBytes.length + hash.length];
+        System.arraycopy(nidBytes, 0, networkHash, 0, nidBytes.length);
+        System.arraycopy(hash, 0, networkHash, nidBytes.length, hash.length);
+        
+        byte[] signature = GajuNative.cryptoSignDetached(networkHash, secretKey);
+        if (signature == null) throw new RuntimeException("Native signing failed");
+        
+        SignedTx signedTx = new SignedTx(List.of(signature), txData);
         return ApiEncoder.encode(ApiEncoder.Type.TRANSACTION, signedTx.serialize());
     }
 }

src/main/java/swiss/qpq/gajumaru/core/tools/VarInt.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2026 QPQ AG <info@qpq.swiss>. All rights reserved.
+ * Project: Gajumaru Core Java Libraries <gajumaru.io>
+ *
+ * This program is dual-licensed:
+ * 1) Under the GNU Affero General Public License as published by the Free
+ *    Software Foundation, either version 3 of the License, or (at your option)
+ *    any later version (AGPL-3.0-or-later).
+ *
+ * 2) Under a commercial/proprietary license available directly from QPQ AG.
+ *    If you wish to use this software outside the strict constraints of the
+ *    AGPLv3 (e.g. within a closed-source or proprietary product), you must
+ *    purchase a commercial license from QPQ AG.
+ *
+ * Authors:
+ *   - Craig Everett <craigeverett@qpq.swiss>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later OR LicenseRef-QPQ-Commercial
+ */
+
+package swiss.qpq.gajumaru.core.tools;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+// Bitcoin-style Variable-length integer encoding.
+// Port of vencode in hz.erl.
+
+public final class VarInt {
+
+    private VarInt() {}
+
+    public static byte[] encode(long n) {
+        if (n < 0) {
+            throw new IllegalArgumentException("Negative values not supported: " + n);
+        }
+        if (n < 0xfd) {
+            return new byte[]{(byte) n};
+        } else if (n <= 0xffff) {
+            ByteBuffer bb = ByteBuffer.allocate(3);
+            bb.order(ByteOrder.LITTLE_ENDIAN);
+            bb.put((byte) 0xfd);
+            bb.putShort((short) n);
+            return bb.array();
+        } else if (n <= 0xffffffffL) {
+            ByteBuffer bb = ByteBuffer.allocate(5);
+            bb.order(ByteOrder.LITTLE_ENDIAN);
+            bb.put((byte) 0xfe);
+            bb.putInt((int) n);
+            return bb.array();
+        } else {
+            ByteBuffer bb = ByteBuffer.allocate(9);
+            bb.order(ByteOrder.LITTLE_ENDIAN);
+            bb.put((byte) 0xff);
+            bb.putLong(n);
+            return bb.array();
+        }
+    }
+}